High Nitrogen Doping of Detonation Nanodiamonds

The main goal of doping detonation nanodiamonds with nitrogen is to obtain stable photoluminescence properties. Small quantities of nitrogen have already been evidenced in such nanodiamonds. This article deals with the possibility of increasing the nitrogen content inside nanodiamond samples. Electron energy loss spectroscopy is a very useful tool for determining the location and the quantity of nitrogen within individual nanodiamonds. The experimental results demonstrate that the nitrogen content strongly depends on the precursors used in the composition of the explosive charge: the incorporation of melamine leads to an increase by a factor 2 or 3 in the nitrogen content in the nanodiamond core. To the best of our knowledge, this is the first time that such high nitrogen contents have been obtained for detonation nanodiamonds. It is also shown that nitrogen is always present inside the nanodiamond core in an sp(3) hybridization configuration.